Recent records of Fusarium wilt of Phoenix canariensis
Fusarium wilt of Phoenix canariensis is caused by Fusarium oxysporum f. sp. canariensis. Affected palms decline from the lower canopy upward to the meristem, and eventually die. Cross sections of vascular tissues show dark discoloration. These symptoms resemble those found on Phoenix dactylifera infected by F. oxysporum f. sp. albedinis (Bayoud disease), but it is now clear that the two pathogens are distinct entities (EPPO RS 97/152). In some parts of the world (e.g. in Australia), significant P. canariensis mortality has been reported. This disease was first observed in France (1970), and then in Italy (first found in Liguria in 1973, and then Marche and Sicilia), Japan (1977), USA (California in 1976, and then Florida and Nevada), Australia (1980s), Morocco (1987), Spain (Islas Canarias in 1987). More recently, the disease has been reported from the following new countries or regions.
First record in Greece (Elena, 2004)
In spring 2002, a severe disease was observed on P. canariensis in Athens county. It rapidly spread between neighbouring trees, and when diseased plants were replaced with new healthy ones they also became infected. Fusarium oxysporum was isolated from the discoloured vascular tissues of the leaves. Tests showed that this fungus was pathogenic to both P. canariensis and P. dactylifera, and could be reisolated from inoculated plants. This is the first report of Fusarium wilt of P. canariensis in Greece.
First record in Sardegna, Italy (Migheli et al., 2005)
In summer 2004, severe wilt symptoms were observed on 25-year-old P. canariensis along the Poetto beach, near Cagliari, in the south of Sardegna. The presence of Fusarium oxysporum f. sp. canariensis was detected in affected plants. The opportunistic pathogen Gliocladium vermoesenii was frequently found in association with it. It is supposed that this outbreak may be related to imports of seedlings from areas where F. oxysporum f.sp. canariensis is widely established.
First record in Argentina (Palmucci, 2005)
In the Buenos Aires province, 2-year-old P. canariensis showed severe wilt of lower leaves and tip death, eventually followed by plant death. Cross sections of vascular tissues showed dark discoloration. Based on morphology, symptoms and pathogenicity tests, the pathogen found on affected palms was considered to be Fusarium oxysporum f. sp. canariensis. This is the first report of this pathogen in Argentina.
Sources
Elena K (2004) Fusarium wilt of Phoenix canariensis: first report in Greece.
New Disease Reports.Volume 10: August 2004 - January 2005
Migheli Q, Balmas V, Muresu M, Otgianu L, Fresu B (2005) First report of Fusarium oxysporum f. sp. canariensis in Sardinia, Italy. Plant Disease 89(7), p 773.
Palmucci HE (2005) Fusarium oxysporum causal agent of wilt on crop fields of Phoenix canariensis in Buenos Aires Province, Argentina
New Disease Reports. Volume 12: August 2005 - January 2006